#include <stdio.h>

int main()
{
    int i,j,a[4],n;
    for(i = 0;i < 4;i++)
    {
        for(j = 0;j < 4;j++)
        if(j == i)
        a[j] = 1;
        else
        a[j] = 0;
        if(a[3] + a[1] == 1 && a[1] + a[2] == 1 && a[0] + a[1] == 1)
        {
            printf("The thief is");
            for(j = 0;j <= 3;j++)
            if(a[j])
            printf(" %c.",j+'A');
            printf("\n");
        }
    }
}